Topical medications that include corticosteroids are used for treating skin conditions such as atopic dermatitis, psoriasis and other pathologies of the skin. Current steroid-containing products are available mainly as gels, lotions or ointments that are supplied in tubes or bottles and applied to an affected area of the skin by hand.
To enhance the effect of a steroid agent on the skin, it is desirable to have a moisturizing or emollient effect to supplement the curative action of the steroid. Also, it is also preferred that an occlusive barrier be applied to the skin during application to enhance the retention and the bioavailability of the steroid.
Current dermatological treatments apply an appropriate amount of a steroid cream or ointment to the skin, and then cover the affected area with a piece of plastic film to provide a barrier to occlude the skin and facilitate the retention of moisture on the skin surface. A commonly used film is composed of a polyvinylidene chloride (PVDC) copolymer and marketed under the trademark Saran.RTM. This way of occluding the surface of the skin, however, is difficult to administer and inconvenient to the patient.
Therefore, it is an object of the present invention to provide a moisturizing lotion for administering a therapeutic agent to the skin while simultaneously forming an occlusive or semi-occlusive barrier on the surface of the skin. Another object is to provide a lotion that will provide enhanced penetration of a therapeutic agent into the skin and a high level of moisturizing activity. Yet another object is to provide a lotion that will adhere to a moist skin surface and provide an occlusive/semi-occlusive barrier.